[MC1600]

I don’t have a 3600 (I have the 4000), but can’t imagine it’s all that different. Once I turn my battery switches on (and check the oil/coolant on the GenSet), I hold the warmup switch for 10 seconds, then start her up.

If I start her from the engine room I then go turn the blower on. If I started her from the panel in the cabin, I typically turn the blower on first.

Since your question was mainly about battery switches, I would think you’d want them all “on.”

Hope this helps!